public class Demo4 {

    public static boolean isFinished = false;

    public static void main(String[] args) throws InterruptedException {


        Thread t = new Thread(() -> {

            while (!isFinished) {
                System.out.println("hello thread");
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    throw new RuntimeException(e);
                }
            }

        });

        t.start();

        for (int i = 0; i < 3; i++) {
            System.out.println("hello main");
            Thread.sleep(1000);
        }

        isFinished = true;

    }
}
